Residual disease after neoadjuvant chemoradiotherapy for oesophageal cancer: locations undetected by endoscopic biopsies in the preSANO trial

Efficacy evaluation and prognostic prediction of endoscopic ultrasound for neoadjuvant immunotherapy in esophageal cancer

BACKGROUND AND OBJECTIVES

Neoadjuvant immunotherapy combined with chemotherapy or chemoradiotherapy has emerged as a promising approach in the treatment of esophageal cancer. However, there is a lack of comprehensive understanding regarding the clinical factors that can predict patient response to this therapy. The aim of this study was to develop a predictive model for assessing the efficacy of neoadjuvant immunotherapy in patients undergoing surgical treatment.

METHODS

This study retrospectively enrolled 220 consecutive patients with preoperative immunotherapy combined chemotherapy or chemoradiotherapy. A logistic regression was used to evaluate the association between pathologic complete response (pCR) and endoscopic ultrasound parameters, constructing a predictive model for treatment response. Additional, overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan-Meier method, and Cox regression analyses were introduced to explore the associations between EUS factors after neoadjuvant immunotherapy.

RESULTS

Logistic regression analysis identified that the significant predictors of pCR were treatment regimen, negative biopsy findings, RECIST assessment, endoscopic ultrasound responder, and downstaging in uN. A predictive model including above five variables was generated, and area under the curve was 0.840(95%CI 0.78-0.89), this nomogram was also adequately validated internally. In the cox regression analyses, EUS responder was found to be a significant predictor of overall survival with a hazard ratio (HR) of 0.38(95%CI 0.15-0.98), whereas only pCR status was a significant predictor of PFS (HR 0.80; 95%CI 0.01-0.60).

CONCLUSIONS

EUS responder can serve as a valuable predictor of the efficacy of adjuvant immunotherapy combined with chemotherapy or chemoradiotherapy, as well as of survival outcomes.

Effects of Neoadjuvant Therapy on Tumour Target Expression of Oesophageal Cancer Tissue for NIR Fluorescence Imaging

PURPOSE

Oesophaegal cancer patients with a clinical complete response (CR) after neoadjuvant chemoradiotherapy (nCRT) are candidates for an active surveillance strategy. Regrowth rates of 40% after initial clinical CR indicate that identification of a true complete response to nCRT remains challenging. Near-infrared tumour-specific fluorescence endoscopic imaging might help to discriminate patients with a true complete response from patients with residual disease. This study aims to find potential markers to enable molecular imaging in oesophageal cancer and to assess the effect of nCRT on marker expression.

PROCEDURES

Oesophageal cancer tissue slides of diagnostic biopsies (n = 41) (pre-treatment) and paired surgical specimens (n = 31) (post-treatment) were collected. Tissue slides of patients with adenocarcinoma (n = 29) and squamous cell carcinoma (n = 12)) were included. Immunohistochemistry was performed to assess expression of the tumour markers CEA, EpCAM, VEGF-α, EGFR, and c-MET in the tumour and compared to the expression of these markers in surrounding healthy tissue. A total immunostaining score (TIS, range 0-12), which combines the percentage and intensity of stained cells, was calculated. The TIS of pre-treated biopsies were compared with the TIS of the post-treatment surgical specimens to assess the effect of neoadjuvant therapy on the marker expression.

RESULTS

The median TIS of EpCAM in adenocarcinomas was 10, vs. 0 in healthy mucosa (p < 0.001). The median TIS of EGFR in squamous cell carcinoma was 12, vs. 4 in healthy mucosa (p < 0.001). Neoadjuvant therapy did not affect the expression of the markers.

CONCLUSION

EpCAM and EGFR appear to be the most suitable targets for tumour-specific NIR fluorescence imaging of oesophageal adenocarcinoma and squamous cell carcinoma, respectively. Unaffected expression of all suitable markers by neoadjuvant therapy implies that the diagnostic biopsy can be used to select a patient-specific target for response evaluation by molecular imaging.

Ultrasound-Guided Quantitative Fluorescence Molecular Endoscopy for Monitoring Response in Patients with Esophageal Cancer Following Neoadjuvant Chemoradiotherapy

PURPOSE

The ability to identify residual tumor tissues in patients with locally advanced esophageal cancer following neoadjuvant chemoradiotherapy (nCRT) is essential for monitoring the treatment response. Using the fluorescent tracer bevacizumab-800CW, we evaluated whether ultrasound-guided quantitative fluorescent molecular endoscopy (US-qFME), which combines quantitative fluorescence molecular endoscopy (qFME) with ultrasound-guided needle biopsy/single-fiber fluorescence (USNB/SFF), can be used to identify residual tumor tissues in patients following nCRT.

EXPERIMENTAL DESIGN

Twenty patients received an additional endoscopy procedure the day before surgery. qFME was performed at the primary tumor site (PTS) and in healthy tissue to first establish the optimal tracer dose. USNB/SFF was then used to measure intrinsic fluorescence in the deeper PTS layers and lymph nodes (LN) suspected for metastasis. Finally, the intrinsic fluorescence and the tissue optical properties-specifically, the absorption and reduced scattering coefficients-were combined into a new parameter called omega.

RESULTS

First, a 25-mg bevacizumab-800CW dose allowed for clear differentiation between the PTS and healthy tissue, with a target-to-background ratio (TBR) of 2.98 (IQR, 1.86-3.03). Moreover, we found a clear difference between the deeper esophageal PTS layers and suspected LN compared to healthy tissues, with TBR values of 2.18 and 2.17, respectively. Finally, our new parameter, omega, further improved the ability to differentiate between the PTS and healthy tissue.

CONCLUSIONS

Combining bevacizumab-800CW with US-qFME may serve as a viable strategy for monitoring the response to nCRT in esophageal cancer and may help stratify patients regarding active surveillance versus surgery.

CT-based deep learning radiomics and hematological biomarkers in the assessment of pathological complete response to neoadjuvant chemoradiotherapy in patients with esophageal squamous cell carcinoma: A two-center study

PURPOSE

To evaluate and validate CT-based models using pre- and posttreatment deep learning radiomics features and hematological biomarkers for assessing esophageal squamous cell carcinoma (ESCC) pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT).

MATERIAL AND METHODS

This retrospective study recruited patients with biopsy-proven ESCC who underwent nCRT from two Chinese hospitals between May 2017 and May 2022, divided into a training set (hospital I, 111 cases), an internal validation set (hospital I, 47 cases), and an external validation set (hospital II, 33 cases). We used minimum redundancy maximum relevance (mRMR) and least absolute shrinkage and selection operator (LASSO) as feature selection methods and three classifiers as model construction methods. The assessment of models was performed using area under the receiver operating characteristic (ROC) curve (AUC) and decision curve analysis (DCA).

RESULTS

A total 190 patients were included in our study (60.8 ± 7.08 years, 133 men), and seventy-seven of them (40.5 %) achieved pCR. The logistic regression (LR)-based combined model incorporating neutrophil to lymphocyte ratio, lymphocyte to monocyte ratio, albumin, and radscores performed well both in the internal and external validation sets with AUCs of 0.875 and 0.857 (95 % CI, 0.776-0.964; 0.731-0.984, P <0.05), respectively. DCA demonstrated that nomogram was useful for pCR prediction and produced clinical net benefits.

CONCLUSION

The incorporation of radscores and hematological biomarkers into LR-based model improved pCR prediction after nCRT in ESCC. Enhanced pCR predictability may improve patients selection before surgery, providing clinical application value for the use of active surveillance.

Combined regression score predicts outcome after neoadjuvant treatment of oesophageal cancer

BACKGROUND

Histopathologic regression following neoadjuvant treatment (NT) of oesophageal cancer is a prognostic factor of survival, but the nodal status is not considered. Here, a score combining both to improve prediction of survival after neoadjuvant therapy is developed.

METHODS

Seven hundred and fifteen patients with oesophageal squamous cell (SCC) or adenocarcinoma (AC) undergoing NT and esophagectomy were analysed. Histopathologic response was classified according to percentage of vital residual tumour cells (VRTC): complete response (CR) without VRTC, major response with <10% VRTC, minor response with >10% VRTC. Nodal stage was classified as ypN0 and ypN+. Kaplan-Meier and Cox regression were used for survival analysis.

RESULTS

Survival analysis identified three groups with significantly different mortality risks: (1) low-risk group for CR (ypT0N0) with 72% 5-year overall survival (5y-OS), (2) intermediate-risk group for minor/major responders and ypN0 with 59% 5y-OS, and (3) high-risk group for minor/major responders and ypN+ with 20% 5y-OS (p < 0.001). Median survival in AC and SCC cohorts were comparable (3.8 (CI 95%: 3.1, 5.3) vs. 4.6 years (CI 95%: 3.3, not reached), p = 0.3).

CONCLUSIONS

Histopathologic regression and nodal status should be combined for estimating AC and SCC prognosis. Poor survival in the high-risk group highlights need for adjuvant therapy.

Residual tumor model in esophageal squamous cell carcinoma after neoadjuvant immunochemotherapy: Frequently involves the mucosa and/or submucosa

Objectives

The efficacy and safety of neoadjuvant immunochemotherapy (nICT) are widely explored in locally advanced esophageal squamous cell carcinoma (ESCC). Whether the "wait-and-see" strategy is applicable in ESCC after nICT is still lacking a theoretical basis. This study aimed to preliminarily explore the distribution of residual tumors and the regression pattern of ESCC after nICT.

Methods

Patients undergoing radical esophagectomy after nICT in Fujian Medical University Union Hospital between January 2020 and March 2022 were identified. The resection specimens were re-evaluated by one experienced pathologist. The pathological response was assessed by tumor regression grade (TRG) (modified Ryan scheme). The TRG grade was divided into grades 0 (pathological complete response), 1, 2, and 3. The pathological stage was evaluated in the Eighth Edition AJCC. In the non-pCR group, the residual model was divided into four types: Type I, regression towards the lumen; type II, regression towards the invasive front; type III, concentric regression; and type IV, scattered regression.

Results

A total of 95 consecutive patients were included for analysis. Seventy-six (80.0%) of 95 patients were in non-pCR (pathological complete response), and nine patients (9/76, 11.84%) had isolated residual tumors in lymph nodes. There was no significant difference in baseline characteristics between the pCR group and the non-pCR group (p > 0.05). The overall distribution of TRG for all esophageal wall layers was TRG 0 = 28 (28/95, 29.5%), TRG 1 = 17 (17/95, 17.9%), TRG 2 = 18 (18.9%, 18/95), and TRG 3 = 32 (32/95, 33.7%). In 67 patients with residual tumors in the esophageal wall (TRG ≧1), 63 (63/67, 94.0%) had residual tumor cells in the mucosa and/or submucosa, and four had isolated residual tumors in the muscle layer (4/67, 6.0%). Further analysis showed eight (8/67, 11.9%) patients with submucosal involvement but without mucosal involvement. The distribution of regression patterns was type I (n = 35, 52.2%), type II (n = 3, 4.5%), type III (n = 8, 11.9%), and type IV (n = 21, 31.3%).

Conclusions

The mucosa and/or submucosa are frequently involved in residual malignancy, and the frequent regression models are regression toward the lumen and random regression. There is an opportunity to carefully test the residual tumors in a subgroup of the population with ESCC following nICT. However, some patients had residual tumors only in the muscle layer or lymph nodes. The clinical application of the wait-and-see strategy in ESCC after nICT should be explored using an appropriate evaluation protocol.

Bite-on-bite biopsies for the detection of residual esophageal cancer after neoadjuvant chemoradiotherapy

BACKGROUND

Active surveillance after neoadjuvant treatment is increasingly implemented. The success of this strategy relies on the accurate detection of residual cancer. This study aimed to assess the diagnostic value of a second (bite-on-bite) biopsy for the detection of residual esophageal cancer and to correlate outcomes to the distribution of residual cancer found in the resection specimen.

METHODS

A multicenter prospective study of esophageal cancer patients undergoing active surveillance after neoadjuvant chemoradiotherapy was performed. At clinical response evaluations, an upper gastrointestinal (GI) endoscopy was performed with at least four bite-on-bite biopsies of the primary tumor site. First and second biopsies were analyzed separately. Patients with histopathological evidence of residual cancer were included in the primary analysis. Two pathologists blinded for biopsy outcome examined all resection specimens.

RESULTS

Between October 2017 and July 2020, 626 upper GI endoscopies were performed in 367 patients. Of 138 patients with residual cancer, 112 patients (81 %) had at least one positive biopsy. In 14 patients (10 %) only the first biopsy was positive and in 25 patients (18 %) only the second biopsy (P = 0.11). Remarkably, the rates of patients with tumor-free mucosa and deeper located tumors were higher in patients detected by the first biopsy. The second biopsy increased the false-positive rate by 3 percentage points. No adverse events occurred.

CONCLUSIONS

A second (bite-on-bite) biopsy improves the detection of residual esophageal cancer by almost 20 percentage points, at the expense of increasing the false-positive rate by 3 percentage points. The higher detection rate is explained by the higher number of biopsies obtained rather than by the penetration depth.

Use of a non-endoscopic immunocytological device (Cytosponge™) for post chemoradiotherapy surveillance in patients with oesophageal cancer in the UK (CYTOFLOC): A multicentre feasibility study

Background

Effective surveillance strategies are required for patients diagnosed with oesophageal squamous cell carcinoma (OSCC) or adenocarcinoma (OAC) for whom chemoradiotherapy (CRT) is used as a potentially-curative, organ-sparing, alternative to surgery. In this study, we evaluated the safety, acceptability and tolerability of a non-endoscopic immunocytological device (the Cytosponge™) to assess treatment response following CRT.

Methods

This multicentre, single-arm feasibility trial took place in 10 tertiary cancer centres in the UK. Patients aged at least 16 years diagnosed with OSCC or OAC, and who were within 4-16 weeks of completing definitive or neo-adjuvant CRT, were included. Participants were required to have a Mellow-Pinkas dysphagia score of 0-2 and be able to swallow tablets. All patients underwent a single Cytosponge™ assessment in addition to standard of care (which included post-treatment endoscopic evaluation with biopsy for patients undergoing definitive CRT; surgery for those who received neo-adjuvant CRT). The primary outcome was the proportion of consented, evaluable patients who successfully underwent Cytosponge™ assessment. Secondary and tertiary outcomes included safety, study consent rate, acceptance rate, the suitability of obtained samples for biomarker analysis, and the comparative efficacy of Cytosponge™ to standard histology (endoscopy and biopsy or post-resection specimen) in assessing for residual disease. The trial is registered with ClinicalTrials.gov, NCT03529669.

Findings

Between 18th April 2018 and 16th January 2020, 41 (42.7%; 95% confidence interval (CI) 32.7-53.2) of 96 potentially eligible patients consented to participate. Thirty-nine (95.1%, 95% CI 83.5-99.4) successfully carried out the Cytosponge™ procedure. Of these, 37 (95%) would be prepared to repeat the procedure. There were only two grade 1 adverse events attributed to use of the Cytosponge™. Thirty-five (90%) of the completed Cytosponge™ samples were suitable for biomarker analysis; 29 (83%) of these were concordant with endoscopic biopsies, three (9%) had findings suggestive of residual cancer on Cytosponge™ not found on endoscopic biopsies, and three (9%) had residual cancer on endoscopic biopsies not detected by Cytosponge™.

Interpretation

Use of the CytospongeTM is safe, tolerable, and acceptable for the assessment of treatment response following CRT in OAC and OSCC. Further evaluation of Cytosponge™ in this setting is warranted.

Funding

Cancer Research UK, National Institute for Health Research, Medical Research Council.

Approach to Localized Squamous Cell Cancer of the Esophagus

OPINION STATEMENT

Esophageal cancer is a leading cause of cancer deaths worldwide, with an increasing incidence in recent decades. The majority of esophageal cancers are squamous cell carcinoma. The 5-year survival rate of esophageal squamous cell carcinoma (ESCC) is poor, and there remains globally a pressing need for novel treatments that improve patient outcomes and quality of life. In this review, we discuss management of localized ESCC with an update on relevant newly published literature, including targeted therapy and novel biomarkers. The standard treatment approach for locally advanced, resectable ESCC is currently chemoradiation with or without surgery. Here we discuss different approaches to endoscopic resection, surgery, and radiation therapy. Although the typical chemotherapy regimen is a combination of a platinum with a fluoropyrimidine or paclitaxel, different regimens are being evaluated. With the landscape of immunotherapy rapidly evolving, at the forefront of new treatments for ESCC is immunotherapy and other targeted agents. Ultimately, the treatment approach should be individualized to each patient.

Long-Term Outcome After Histopathological Complete Response with and Without Nodal Metastases Following Multimodal Treatment of Esophageal Cancer

BACKGROUND

This study analyzed the long-term survival after pathological complete response (pCR) with and without nodal metastases and associated recurrence following multimodal treatment of esophageal cancer. The recurrence pattern after pCR is of importance for different postoperative surveillance strategies.

METHODS

A cohort of 890 patients with esophageal cancer received neoadjuvant therapy followed by transthoracic esophagectomy. Only patients with pCR of the primary tumor with and without nodal metastasis were analyzed. A clinicopathological database was set up and completed with long-term follow up information on recurrent disease.

RESULTS

The specimen of 201 patients (23%) demonstrated pCR, 84% without (ypT0N0) and 16% with residual nodal disease (ypT0N+). For ypT0N0 patients, the 5-year overall survival was significantly higher than for patients with metastatic nodes (77% vs. 24%) (p < 0.0001). Sixty-eight percent of patients had no evidence of tumor recurrence, whereas 32% had proven relapse. For patients with and without tumor recurrence, 5-year survival rates were 14% and 93%, respectively (p < 0.0001). For patients with recurrent disease, median survival time was 27 for locoregional, 44 for distant, and 24 months for combined recurrence (p = 0.302). In the multivariable Cox-regression analysis, node-positive disease predicted both locoregional and metastatic recurrence.

CONCLUSIONS

Pathological CR offers long-term survival in patients without nodal metastases but outcome significantly deteriorates with the presence of nodal metastases. Follow-up recommendations may therefore be adopted in patients with pCR. Furthermore, "watch-and-wait" surveillance strategies with suspected clinical complete response have to be considered with caution.

Predictive value of endoscopic esophageal findings for residual esophageal cancer after neoadjuvant chemoradiotherapy

BACKGROUND

Endoscopic evaluation of the esophageal mucosa may play a role in an active surveillance strategy after neoadjuvant chemoradiotherapy (nCRT) for esophageal cancer. This study investigated the yield of endoscopic findings for detection of residual disease.

METHODS

Patients from the multicenter preSANO cohort, who underwent nCRT followed by surgery for esophageal or junctional cancer, were included. Upper endoscopy was performed 6 and 12 weeks after nCRT. Patients with residual disease at 6 weeks underwent immediate surgery. Endoscopic records were reviewed for presence of stenosis, suspicion of residual tumor, scar tissue, and ulceration. Presence and type of endoscopic findings were compared with outcome of the resection specimen.

RESULTS

118 of 156 patients (76 %) had residual disease in the resection specimen. Endoscopic suspicion of residual tumor was significantly associated with presence of residual disease. At 6 weeks, 40/112 patients with residual disease and 4/33 patients with complete response had endoscopic suspicion of residual tumor (36 % vs. 12 %; P = 0.01), while this was reported in 16/73 and 0/28 patients, respectively, at 12 weeks (22 % vs. 0 %; P < 0.01). Positive predictive value of endoscopic suspicion of residual tumor was 91 % at 6 weeks and 100 % at 12 weeks. Endoscopic findings of non-passable stenosis, passable stenosis, scar tissue, or ulceration were not associated with residual disease.

CONCLUSIONS

Endoscopic suspicion of residual tumor was the only endoscopic finding associated with residual disease. Based on its positive predictive value, this endoscopic finding may contribute to the diagnostic strategy used in active surveillance.

Organ preservation in the multimodality approach to locally advanced oesophageal cancer: festina lente

Morbidity and impacts on quality of life remain significant issues following oesophagectomy for oesophageal cancer. This paper reviews and weighs the current evidence both in favour of and against the adoption of an organ-preserving approach in patients with a complete clinical response to neoadjuvant therapy.